So since 5.24 came out I've had two build ideas I've thought of, a Pact of the Blade GOOlock with Polearm Master and Shillelagh, and an Assassin Rogue (8)/Vengeance Paladin(12). I am, however, unsure how certain aspects of the build concepts stack. I'll spoiler the relevant rules text beneath each of the builds, for ease of access.
Warlock - Would a 17th level warlock with a Quarterstaff as their pact weapon, who took the following Invocations: Thirsting Blade, Devouring Blade, and either Pact of the Tome or Lesson of the First Ones (for Magic Initiate Druid), do three attacks with the attack action, each doing 2d6 from the cantrip-scaling shillelagh, and a possible bonus action attack from Polearm Master's Pole Strike feature, also doing 2d6 (replacing the damage die due to shillelagh). In addition, would you have the choice of Necrotic, Psychic, Radiant (from Pact of the the Blade) and Force (Shillelagh) or once you made the Pact Weapon a Shillelagh, would you lose the ability to choose the Pact of the Blade damage types?
Pact of the Blade As a Bonus Action, you can conjure a pact weapon in your hand—a Simple or Martial Melee weapon of your choice with which you bond—or create a bond with a magic weapon you touch; you can’t bond with a magic weapon if someone else is attuned to it or another Warlock is bonded with it. Until the bond ends, you have proficiency with the weapon, and you can use it as a Spellcasting Focus.
Whenever you attack with the bonded weapon, you can use your Charisma modifier for the attack and damage rolls instead of using Strength or Dexterity; and you can cause the weapon to deal Necrotic, Psychic, or Radiant damage or its normal damage type.
Your bond with the weapon ends if you use this feature’s Bonus Action again, if the weapon is more than 5 feet away from you for 1 minute or more, or if you die. A conjured weapon disappears when the bond ends.
Thirsting Blade Prerequisite: Level 5+ Warlock, Pact of the Blade Invocation
You gain the Extra Attack feature for your pact weapon only. With that feature, you can attack twice with the weapon instead of once when you take the Attack action on your turn.
The Extra Attack of your Thirsting Blade invocation confers two extra attacks rather than one.
Shillelagh Transmutation Cantrip (Druid)
Casting Time: Bonus Action
Range: Self
Components: V, S, M (mistletoe)
Duration: 1 minute
A Club or Quarterstaff you are holding is imbued with nature’s power. For the duration, you can use your spellcasting ability instead of Strength for the attack and damage rolls of melee attacks using that weapon, and the weapon’s damage die becomes a d8. If the attack deals damage, it can be Force damage or the weapon’s normal damage type (your choice).
The spell ends early if you cast it again or if you let go of the weapon.
Cantrip Upgrade. The damage die changes when you reach levels 5 (d10), 11 (d12), and 17 (2d6).
Polearm Master General Feat (Prerequisite: Level 4+, Strength or Dexterity 13+)
You gain the following benefits.
Ability Score Increase. Increase your Dexterity or Strength score by 1, to a maximum of 20.
Pole Strike. Immediately after you take the Attack action and attack with a Quarterstaff, a Spear, or a weapon that has the Heavy and Reach properties, you can use a Bonus Action to make a melee attack with the opposite end of the weapon. The weapon deals Bludgeoning damage, and the weapon’s damage die for this attack is a d4.
Reactive Strike. While you’re holding a Quarterstaff, a Spear, or a weapon that has the Heavy and Reach properties, you can take a Reaction to make one melee attack against a creature that enters the reach you have with that weapon.
Rogue/Paladin - Essentially, how many attacks would a Hasted, Rapier and Dagger (or Scimitar, both have Nick property) wielding, Rogue/Paladin with the Dual Wielder Feat, with the applicable weapon masteries make, and more specifically does attack order matter? Could you do Rapier (damage die + ability modifier), Rapier (damage die + ability modifier), Nick Weapon attack (damage die without ability modifier), Hasted attack (unsure if you'd also get to do Nick attack with this one, and also unsure which weapon it'd have to be with, as well as if it has the ability modifier), Dual Wielder Bonus Action attack (unsure which weapon this attack would be with too, but it's fairly clear it wouldn't have ability modifier, but I could be wrong) or would the Rapier have to be the offhand attack?
Haste Level 3 Transmutation (Sorcerer, Wizard)
Casting Time: Action
Range: 30 feet
Components: V, S, M (a shaving of licorice root)
Duration: Concentration, up to 1 minute
Choose a willing creature that you can see within range. Until the spell ends, the target’s Speed is doubled, it gains a +2 bonus to Armor Class, it has Advantage on Dexterity saving throws, and it gains an additional action on each of its turns. That action can be used to take only the Attack (one attack only), Dash, Disengage, Hide, or Utilize action.
When the spell ends, the target is Incapacitated and has a Speed of 0 until the end of its next turn, as a wave of lethargy washes over it.
Dagger 1d4 Piercing Finesse, Light, Thrown (Range 20/60) Nick
Rapier 1d8 Piercing Finesse Vex
Scimitar 1d6 Slashing Finesse, Light Nick
Nick When you make the extra attack of the Light property, you can make it as part of the Attack action instead of as a Bonus Action. You can make this extra attack only once per turn.
Vex If you hit a creature with this weapon and deal damage to the creature, you have Advantage on your next attack roll against that creature before the end of your next turn.
Dual Wielder General Feat (Prerequisite: Level 4+, Strength or Dexterity 13+)
You gain the following benefits.
Ability Score Increase. Increase your Strength or Dexterity score by 1, to a maximum of 20.
Enhanced Dual Wielding. When you take the Attack action on your turn and attack with a weapon that has the Light property, you can make one extra attack as a Bonus Action later on the same turn with a different weapon, which must be a Melee weapon that lacks the Two-Handed property. You don’t add your ability modifier to the extra attack’s damage unless that modifier is negative.
Quick Draw. You can draw or stow two weapons that lack the Two-Handed property when you would normally be able to draw or stow only one.
I apologize in advance if these are fairly simple concepts and the answer is obvious, I may just be overcomplicating things for myself.
Edit: A further question, can you no longer "bamf" your Pact Weapon (assuming it's a magic weapon, and not a conjured one) to your hand like you used to be able to do in 5.14, (and like Fjord did often in Critical Role Campaign 2), or am I missing an obvious bit of rules text, therein?
For the Warlock - the BA attack would still be a d4, and the damage would always been Force if you are using Shillelagh. You use a bonus action to "bamf" the weapon into your hand.
For the Paladin/Rogue - Haste = 1 rapier attack, Attack Action = 1 rapier attack + 2x scimitar attacks (using Nick), Bonus Action = 1 rapier attack (Dual Wielder). The Bonus Action and Nick-scimitar attack must occur after the first scimitar attack. If you have the Two Weapon Fighting, Fighting Style, then the Nick-scimitar attack definitely adds your ability modifier and the Dual Wielder Bonus Action maybe is supposed to add it as well?
So since 5.24 came out I've had two build ideas I've thought of, a Pact of the Blade GOOlock with Polearm Master and Shillelagh, and an Assassin Rogue (8)/Vengeance Paladin(12). I am, however, unsure how certain aspects of the build concepts stack. I'll spoiler the relevant rules text beneath each of the builds, for ease of access.
Warlock - Would a 17th level warlock with a Quarterstaff as their pact weapon, who took the following Invocations: Thirsting Blade, Devouring Blade, and either Pact of the Tome or Lesson of the First Ones (for Magic Initiate Druid), do three attacks with the attack action, each doing 2d6 from the cantrip-scaling shillelagh, and a possible bonus action attack from Polearm Master's Pole Strike feature, also doing 2d6 (replacing the damage die due to shillelagh). In addition, would you have the choice of Necrotic, Psychic, Radiant (from Pact of the the Blade) and Force (Shillelagh) or once you made the Pact Weapon a Shillelagh, would you lose the ability to choose the Pact of the Blade damage types?
Pact of the Blade As a Bonus Action, you can conjure a pact weapon in your hand—a Simple or Martial Melee weapon of your choice with which you bond—or create a bond with a magic weapon you touch; you can’t bond with a magic weapon if someone else is attuned to it or another Warlock is bonded with it. Until the bond ends, you have proficiency with the weapon, and you can use it as a Spellcasting Focus.
Whenever you attack with the bonded weapon, you can use your Charisma modifier for the attack and damage rolls instead of using Strength or Dexterity; and you can cause the weapon to deal Necrotic, Psychic, or Radiant damage or its normal damage type.
Your bond with the weapon ends if you use this feature’s Bonus Action again, if the weapon is more than 5 feet away from you for 1 minute or more, or if you die. A conjured weapon disappears when the bond ends.
Thirsting Blade Prerequisite: Level 5+ Warlock, Pact of the Blade Invocation
You gain the Extra Attack feature for your pact weapon only. With that feature, you can attack twice with the weapon instead of once when you take the Attack action on your turn.
The Extra Attack of your Thirsting Blade invocation confers two extra attacks rather than one.
Shillelagh Transmutation Cantrip (Druid)
Casting Time: Bonus Action
Range: Self
Components: V, S, M (mistletoe)
Duration: 1 minute
A Club or Quarterstaff you are holding is imbued with nature’s power. For the duration, you can use your spellcasting ability instead of Strength for the attack and damage rolls of melee attacks using that weapon, and the weapon’s damage die becomes a d8. If the attack deals damage, it can be Force damage or the weapon’s normal damage type (your choice).
The spell ends early if you cast it again or if you let go of the weapon.
Cantrip Upgrade. The damage die changes when you reach levels 5 (d10), 11 (d12), and 17 (2d6).
Polearm Master General Feat (Prerequisite: Level 4+, Strength or Dexterity 13+)
You gain the following benefits.
Ability Score Increase. Increase your Dexterity or Strength score by 1, to a maximum of 20.
Pole Strike. Immediately after you take the Attack action and attack with a Quarterstaff, a Spear, or a weapon that has the Heavy and Reach properties, you can use a Bonus Action to make a melee attack with the opposite end of the weapon. The weapon deals Bludgeoning damage, and the weapon’s damage die for this attack is a d4.
Reactive Strike. While you’re holding a Quarterstaff, a Spear, or a weapon that has the Heavy and Reach properties, you can take a Reaction to make one melee attack against a creature that enters the reach you have with that weapon.
It would work but it's not the optimum choice. If you're getting PAM then you have STR or DEX 13, if you get STR 13 then you can also pick-up GWM and GWM adds far more damage than Shillelagh would, you'd just have to use a polearm with the heavy property. Pole Strike is always a D4, this can not be overridden.
Rogue/Paladin - Essentially, how many attacks would a Hasted, Rapier and Dagger (or Scimitar, both have Nick property) wielding, Rogue/Paladin with the Dual Wielder Feat, with the applicable weapon masteries make, and more specifically does attack order matter? Could you do Rapier (damage die + ability modifier), Rapier (damage die + ability modifier), Nick Weapon attack (damage die without ability modifier), Hasted attack (unsure if you'd also get to do Nick attack with this one, and also unsure which weapon it'd have to be with, as well as if it has the ability modifier), Dual Wielder Bonus Action attack (unsure which weapon this attack would be with too, but it's fairly clear it wouldn't have ability modifier, but I could be wrong) or would the Rapier have to be the offhand attack?
Haste Level 3 Transmutation (Sorcerer, Wizard)
Casting Time: Action
Range: 30 feet
Components: V, S, M (a shaving of licorice root)
Duration: Concentration, up to 1 minute
Choose a willing creature that you can see within range. Until the spell ends, the target’s Speed is doubled, it gains a +2 bonus to Armor Class, it has Advantage on Dexterity saving throws, and it gains an additional action on each of its turns. That action can be used to take only the Attack (one attack only), Dash, Disengage, Hide, or Utilize action.
When the spell ends, the target is Incapacitated and has a Speed of 0 until the end of its next turn, as a wave of lethargy washes over it.
Dagger 1d4 Piercing Finesse, Light, Thrown (Range 20/60) Nick
Rapier 1d8 Piercing Finesse Vex
Scimitar 1d6 Slashing Finesse, Light Nick
Nick When you make the extra attack of the Light property, you can make it as part of the Attack action instead of as a Bonus Action. You can make this extra attack only once per turn.
Vex If you hit a creature with this weapon and deal damage to the creature, you have Advantage on your next attack roll against that creature before the end of your next turn.
Dual Wielder General Feat (Prerequisite: Level 4+, Strength or Dexterity 13+)
You gain the following benefits.
Ability Score Increase. Increase your Strength or Dexterity score by 1, to a maximum of 20.
Enhanced Dual Wielding. When you take the Attack action on your turn and attack with a weapon that has the Light property, you can make one extra attack as a Bonus Action later on the same turn with a different weapon, which must be a Melee weapon that lacks the Two-Handed property. You don’t add your ability modifier to the extra attack’s damage unless that modifier is negative.
Quick Draw. You can draw or stow two weapons that lack the Two-Handed property when you would normally be able to draw or stow only one.
I apologize in advance if these are fairly simple concepts and the answer is obvious, I may just be overcomplicating things for myself.
Edit: A further question, can you no longer "bamf" your Pact Weapon (assuming it's a magic weapon, and not a conjured one) to your hand like you used to be able to do in 5.14, (and like Fjord did often in Critical Role Campaign 2), or am I missing an obvious bit of rules text, therein?
You can't use a rapier with TWF/Light Property as Rapier does not have the light property (which makes sense as in real life a Rapier is about as heavy as a long sword), you could use it with Dual Wielder for the BA attack but it's getting into weapon juggling and I'm not too fond of that personally.
With a Shortsword and Scimitar, you should get 1 attack from all of the following
So this would give you 5 attacks, however Haste here is a bad choice. Haste takes an action too cast, if you cast it on yourself (Oath of Glory or Oath of Vengeance), you lose 4 attacks to cast Haste, you'd need 5 rounds of combat just to catch up on number of attacks. If you're asking somebody else to cast it on you, are you sure there isn't something more meaningful and impactful they can do with a 3rd level spell slot over concentrating on a buff just for you? I mean Fireball is a 3rd level spell and does far more than Haste does. The only time Haste makes sense is if you can cast it before combat but it's hard to both cast Haste and not ruin stealth, where Surprise is still better than haste.
As for weapons, I'd just stick with Shortsword and Scimitar, I am not a fan of all these weird weapon juggling builds people are coming up with. People are using three swords like they are Zoro from One Piece.
As for Oath, Oath of Vengeance gives Vow of Enmity, which gives advantage, meaning you don't even need a Vex weapon any more, you just straight up get advantage from the channel divinity.
The d4 bonus action attack with base of the quarterstaff is weapon damage of the quarter staff (or arguably improvised weapon damage of the staff) albeit due to a feat and thus may be overridden by Shillelagh RAW.
Shillelagh is a damage dealing cantrip- if obtained via book of shadows it is a warlock cantrip and thus may be eligible for agonising blast (to add additional cha damage) and repelling blast (push 10ft on a hit)
You can't use a rapier with TWF/Light Property as Rapier does not have the light property (which makes sense as in real life a Rapier is about as heavy as a long sword),
IRL. Rapier averages around 2 lbs, and longswords average around 4 - 6 lbs. That's more than two to three times the weight. Their weights aren't similar at all, again IRL. I've used and train with both, they are no where near similar in weight. That 2 lbs makes a huge bit of difference.
The game rules under weigh the Longsword at 3 (underweighted imo especially with the versatile trait), Scimitar at 3, and Rapier at 2. With only the Scimitar getting the light property which makes no sense what so ever. The Game rules for weapon weights and properties are completely inconsistent. Personally I'd very likely house rule Rapiers as having the light property. If the OP's the player, show your GM the data inconsistency and see if they'd house rule it too.
But by RAW Rapiers are not light weapons. Personally I think the RAW and RAI are conflicted here. Rapiers and Scimitars were both meant to be lighter nimbler weapons than the Longsword. I wouldn't be surprised if this gets errata'd.
The d4 bonus action attack with base of the quarterstaff is weapon damage of the quarter staff (or arguably improvised weapon damage of the staff) albeit due to a feat and thus may be overridden by Shillelagh RAW.
This was answered in the SAC:
If I cast shillelagh on my quarterstaff and have the Polearm Master feat, does the bonus attack use a d4 or a d8 for damage?
The benefit from Polearm Master applies to the opposite end of the weapon and always uses a d4 for damage rather than the weapon’s normal damage die. This is true for a quarterstaff enhanced with shillelagh just as it is for a normal one.
Shillelagh is a damage dealing cantrip- if obtained via book of shadows it is a warlock cantrip and thus may be eligible for agonising blast (to add additional cha damage) and repelling blast (push 10ft on a hit)
There's debate across the forum about how Shillelagh interacts with Agonizing Blast, but I don't think it works. The damage from Shillelagh comes from the weapon, not the spell itself, which is what Agonizing Blast requires.
But by RAW Rapiers are not light weapons. Personally I think the RAW and RAI are conflicted here. Rapiers and Scimitars were both meant to be lighter nimbler weapons than the Longsword. I wouldn't be surprised if this gets errata'd.
It won't be errata'd, these weapon stats have been the same for a long time (apart from the recently added mastery properties) and they have stayed the same for a reason.
D&D weapon names aren't really much connected to reality, they are mainly vehicles to deliver some specified statistics (a damage die + some properties). So a Rapier is D8 + Finesse while a Scimitar is D6 + Finesse + Light. This means that Rapiers and Scimitars combines differently with other rules but that is the whole point of them being different weapons (and this is why I wouldn't give them the same properties).
So since 5.24 came out I've had two build ideas I've thought of, a Pact of the Blade GOOlock with Polearm Master and Shillelagh, and an Assassin Rogue (8)/Vengeance Paladin(12). I am, however, unsure how certain aspects of the build concepts stack. I'll spoiler the relevant rules text beneath each of the builds, for ease of access.
Warlock - Would a 17th level warlock with a Quarterstaff as their pact weapon, who took the following Invocations: Thirsting Blade, Devouring Blade, and either Pact of the Tome or Lesson of the First Ones (for Magic Initiate Druid), do three attacks with the attack action, each doing 2d6 from the cantrip-scaling shillelagh, and a possible bonus action attack from Polearm Master's Pole Strike feature, also doing 2d6 (replacing the damage die due to shillelagh). In addition, would you have the choice of Necrotic, Psychic, Radiant (from Pact of the the Blade) and Force (Shillelagh) or once you made the Pact Weapon a Shillelagh, would you lose the ability to choose the Pact of the Blade damage types?
Pact of the Blade
As a Bonus Action, you can conjure a pact weapon in your hand—a Simple or Martial Melee weapon of your choice with which you bond—or create a bond with a magic weapon you touch; you can’t bond with a magic weapon if someone else is attuned to it or another Warlock is bonded with it. Until the bond ends, you have proficiency with the weapon, and you can use it as a Spellcasting Focus.
Whenever you attack with the bonded weapon, you can use your Charisma modifier for the attack and damage rolls instead of using Strength or Dexterity; and you can cause the weapon to deal Necrotic, Psychic, or Radiant damage or its normal damage type.
Your bond with the weapon ends if you use this feature’s Bonus Action again, if the weapon is more than 5 feet away from you for 1 minute or more, or if you die. A conjured weapon disappears when the bond ends.
Thirsting Blade
Prerequisite: Level 5+ Warlock, Pact of the Blade Invocation
You gain the Extra Attack feature for your pact weapon only. With that feature, you can attack twice with the weapon instead of once when you take the Attack action on your turn.
Devouring Blade
Prerequisite: Level 12+ Warlock, Thirsting Blade Invocation
The Extra Attack of your Thirsting Blade invocation confers two extra attacks rather than one.
Shillelagh
Transmutation Cantrip (Druid)
Casting Time: Bonus Action
Range: Self
Components: V, S, M (mistletoe)
Duration: 1 minute
A Club or Quarterstaff you are holding is imbued with nature’s power. For the duration, you can use your spellcasting ability instead of Strength for the attack and damage rolls of melee attacks using that weapon, and the weapon’s damage die becomes a d8. If the attack deals damage, it can be Force damage or the weapon’s normal damage type (your choice).
The spell ends early if you cast it again or if you let go of the weapon.
Cantrip Upgrade. The damage die changes when you reach levels 5 (d10), 11 (d12), and 17 (2d6).
Polearm Master
General Feat (Prerequisite: Level 4+, Strength or Dexterity 13+)
You gain the following benefits.
Ability Score Increase. Increase your Dexterity or Strength score by 1, to a maximum of 20.
Pole Strike. Immediately after you take the Attack action and attack with a Quarterstaff, a Spear, or a weapon that has the Heavy and Reach properties, you can use a Bonus Action to make a melee attack with the opposite end of the weapon. The weapon deals Bludgeoning damage, and the weapon’s damage die for this attack is a d4.
Reactive Strike. While you’re holding a Quarterstaff, a Spear, or a weapon that has the Heavy and Reach properties, you can take a Reaction to make one melee attack against a creature that enters the reach you have with that weapon.
Rogue/Paladin - Essentially, how many attacks would a Hasted, Rapier and Dagger (or Scimitar, both have Nick property) wielding, Rogue/Paladin with the Dual Wielder Feat, with the applicable weapon masteries make, and more specifically does attack order matter? Could you do Rapier (damage die + ability modifier), Rapier (damage die + ability modifier), Nick Weapon attack (damage die without ability modifier), Hasted attack (unsure if you'd also get to do Nick attack with this one, and also unsure which weapon it'd have to be with, as well as if it has the ability modifier), Dual Wielder Bonus Action attack (unsure which weapon this attack would be with too, but it's fairly clear it wouldn't have ability modifier, but I could be wrong) or would the Rapier have to be the offhand attack?
Haste
Level 3 Transmutation (Sorcerer, Wizard)
Casting Time: Action
Range: 30 feet
Components: V, S, M (a shaving of licorice root)
Duration: Concentration, up to 1 minute
Choose a willing creature that you can see within range. Until the spell ends, the target’s Speed is doubled, it gains a +2 bonus to Armor Class, it has Advantage on Dexterity saving throws, and it gains an additional action on each of its turns. That action can be used to take only the Attack (one attack only), Dash, Disengage, Hide, or Utilize action.
When the spell ends, the target is Incapacitated and has a Speed of 0 until the end of its next turn, as a wave of lethargy washes over it.
Dagger 1d4 Piercing Finesse, Light, Thrown (Range 20/60) Nick
Rapier 1d8 Piercing Finesse Vex
Scimitar 1d6 Slashing Finesse, Light Nick
Nick
When you make the extra attack of the Light property, you can make it as part of the Attack action instead of as a Bonus Action. You can make this extra attack only once per turn.
Vex
If you hit a creature with this weapon and deal damage to the creature, you have Advantage on your next attack roll against that creature before the end of your next turn.
Dual Wielder
General Feat (Prerequisite: Level 4+, Strength or Dexterity 13+)
You gain the following benefits.
Ability Score Increase. Increase your Strength or Dexterity score by 1, to a maximum of 20.
Enhanced Dual Wielding. When you take the Attack action on your turn and attack with a weapon that has the Light property, you can make one extra attack as a Bonus Action later on the same turn with a different weapon, which must be a Melee weapon that lacks the Two-Handed property. You don’t add your ability modifier to the extra attack’s damage unless that modifier is negative.
Quick Draw. You can draw or stow two weapons that lack the Two-Handed property when you would normally be able to draw or stow only one.
I apologize in advance if these are fairly simple concepts and the answer is obvious, I may just be overcomplicating things for myself.
Edit: A further question, can you no longer "bamf" your Pact Weapon (assuming it's a magic weapon, and not a conjured one) to your hand like you used to be able to do in 5.14, (and like Fjord did often in Critical Role Campaign 2), or am I missing an obvious bit of rules text, therein?
I’m not sure, I’ll have to do some research.
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For the Warlock - the BA attack would still be a d4, and the damage would always been Force if you are using Shillelagh. You use a bonus action to "bamf" the weapon into your hand.
For the Paladin/Rogue - Haste = 1 rapier attack, Attack Action = 1 rapier attack + 2x scimitar attacks (using Nick), Bonus Action = 1 rapier attack (Dual Wielder). The Bonus Action and Nick-scimitar attack must occur after the first scimitar attack. If you have the Two Weapon Fighting, Fighting Style, then the Nick-scimitar attack definitely adds your ability modifier and the Dual Wielder Bonus Action maybe is supposed to add it as well?
It would work but it's not the optimum choice. If you're getting PAM then you have STR or DEX 13, if you get STR 13 then you can also pick-up GWM and GWM adds far more damage than Shillelagh would, you'd just have to use a polearm with the heavy property. Pole Strike is always a D4, this can not be overridden.
You can't use a rapier with TWF/Light Property as Rapier does not have the light property (which makes sense as in real life a Rapier is about as heavy as a long sword), you could use it with Dual Wielder for the BA attack but it's getting into weapon juggling and I'm not too fond of that personally.
With a Shortsword and Scimitar, you should get 1 attack from all of the following
Main Action - Attack Action (light+vex weapon)
Main Action - Extra attack (Any weapon?)
Main Action - Nick (light+nick weapon)
Bonus Action - Dual Wielder Feat (non-two handed melee weapon)
Haste - Attack Action (Any weapon)
So this would give you 5 attacks, however Haste here is a bad choice. Haste takes an action too cast, if you cast it on yourself (Oath of Glory or Oath of Vengeance), you lose 4 attacks to cast Haste, you'd need 5 rounds of combat just to catch up on number of attacks. If you're asking somebody else to cast it on you, are you sure there isn't something more meaningful and impactful they can do with a 3rd level spell slot over concentrating on a buff just for you? I mean Fireball is a 3rd level spell and does far more than Haste does. The only time Haste makes sense is if you can cast it before combat but it's hard to both cast Haste and not ruin stealth, where Surprise is still better than haste.
As for weapons, I'd just stick with Shortsword and Scimitar, I am not a fan of all these weird weapon juggling builds people are coming up with. People are using three swords like they are Zoro from One Piece.
As for Oath, Oath of Vengeance gives Vow of Enmity, which gives advantage, meaning you don't even need a Vex weapon any more, you just straight up get advantage from the channel divinity.
Some 5.5 arguable's here:
The d4 bonus action attack with base of the quarterstaff is weapon damage of the quarter staff (or arguably improvised weapon damage of the staff) albeit due to a feat and thus may be overridden by Shillelagh RAW.
Shillelagh is a damage dealing cantrip- if obtained via book of shadows it is a warlock cantrip and thus may be eligible for agonising blast (to add additional cha damage) and repelling blast (push 10ft on a hit)
IRL. Rapier averages around 2 lbs, and longswords average around 4 - 6 lbs. That's more than two to three times the weight. Their weights aren't similar at all, again IRL. I've used and train with both, they are no where near similar in weight. That 2 lbs makes a huge bit of difference.
The game rules under weigh the Longsword at 3 (underweighted imo especially with the versatile trait), Scimitar at 3, and Rapier at 2. With only the Scimitar getting the light property which makes no sense what so ever. The Game rules for weapon weights and properties are completely inconsistent. Personally I'd very likely house rule Rapiers as having the light property. If the OP's the player, show your GM the data inconsistency and see if they'd house rule it too.
But by RAW Rapiers are not light weapons. Personally I think the RAW and RAI are conflicted here. Rapiers and Scimitars were both meant to be lighter nimbler weapons than the Longsword. I wouldn't be surprised if this gets errata'd.
This was answered in the SAC:
There's debate across the forum about how Shillelagh interacts with Agonizing Blast, but I don't think it works. The damage from Shillelagh comes from the weapon, not the spell itself, which is what Agonizing Blast requires.
Some related threads:
It won't be errata'd, these weapon stats have been the same for a long time (apart from the recently added mastery properties) and they have stayed the same for a reason.
D&D weapon names aren't really much connected to reality, they are mainly vehicles to deliver some specified statistics (a damage die + some properties). So a Rapier is D8 + Finesse while a Scimitar is D6 + Finesse + Light. This means that Rapiers and Scimitars combines differently with other rules but that is the whole point of them being different weapons (and this is why I wouldn't give them the same properties).